Linux system build for the Neo FreeRunner with Buildroot
This project is a set of patches and configuration files for Buildroot to build a Linux system image with a minimal root file system for the great Openmoko Neo FreeRunner (GTA02).
Build
The first step is to get the files required to run Buildroot:
$ make bootstrap
Then build the images with:
$ make build
After the build, the directory buildroot/output/images/ contains
- the U-Boot image
u-boot.udfu - the Linux kernel image for U-Boot
uImage - the JFFS2 root file system for the NAND
rootfs.jffs2
Flash the system
Internal NAND flash
The images can be flashed with dfu-util by following with standard Neo FreeRunner flashing instructions or by using:
$ make flash
SD card
The SD card partitioning is described in Booting the Neo FreeRunner from SD via U-Boot.
The kernel must be copied from buildroot/output/images/uImage to the first SD card partition (FAT) under the name uImage.bin. The content of the root file system archive buildroot/output/images/rootfs.tar.gz must be extracted in the second SD card partition (ext2).
Run
To boot U-Boot just flashed into the NAND above, press and hold Power button then while still pressing the Power button, press and hold AUX button for 5 to 8 seconds. To boot U-Boot from the NOR, press and hold the AUX button, while still pressing the AUX button, press and hold the Power button, then release the AUX button.
See complete instructions in Booting the Neo FreeRunner via U-Boot.
Configure a custom build
Packages
The image content can be configured in Buildroot with:
$ make -C buildroot/ menuconfig
Boot loader splash screen
To generate an OpenMoko splash screen in the correct format:
$ make splash
Then add the splashimage variable to the NAND U-Boot:
setenv splashimage nand read.e 0x32000000 splash 0x5000\; unzip 0x32000000 0x8800000 0x96000
saveenv
This splashimage command loads a maximum compressed splash size of 0x5000 which is 20480 bytes. The file should be smaller than that or the size increase in the U-Boot read command.
See complete instructions in Configuring the boot splash screens.
Network
The IP configuration for the USB gadget ethernet interface resides in overlay/etc/network/interfaces. A custom SSID and PSK for the wifi can be added in overlay/etc/wpa_supplicant.conf.
NAND U-Boot menu
The default U-Boot environment can be loaded with defaultenv. Parameters can be passed from the boot loader to runtime with kernel parameters:
setenv menu_1 Boot from microSD (FAT+ext2): setenv bootargs ${bootargs_base} rootfstype=ext2 root=/dev/mmcblk0p2 rootdelay=5 ${mtdparts} ro\; mmcinit\; fatload mmc 1 0x32000000 ${sd_image_name}\; bootm 0x32000000
setenv menu_4 Boot (USB host mode, Wi-Fi on, graphics off): setenv bootargs_base ${bootargs_base} bootwifi=on bootusb=host bootgraphics=off\; run bootcmd
setenv menu_5 Boot (USB host mode, Wi-Fi on, graphics on): setenv bootargs_base ${bootargs_base} bootwifi=on bootusb=host bootgraphics=on\; run bootcmd
setenv menu_6 Reboot: reset
setenv menu_8 Power off: neo1973 power-off
saveenv
Support
✔️ Build kernel
✔️ Build root file system (JFFS2 in flash)
✔️ Build root file system (SD card)
✔️ Build boot loader
✔️ Boot loader splash screen
✔️ Display (console in frame buffer /dev/fb0)
✔️ Display (Xorg with xdriver_xf86-video-fbdev, tested with fluxbox)
✔️ Touch screen (/dev/input/mouse0 output, also working under Xorg)
✔️ Backlight control
✔️ USB host mode
✔️ USB gadget (Ethernet)
✔️ Wi-Fi WPA2/PSK (STA, AP not supported in driver)
✔️ Bluetooth (USB host mode then echo 1 > /sys/bus/platform/drivers/gta02-pm-bt/gta02-pm-bt.0/power_on then hciconfig hci0 up then hcitool scan)
✔️ GPS (NMEA messages coming on /dev/ttySAC1, gpsd working)
✔️ SD card
✔️ Accelerometers (/dev/input/event3, test code here)
✔️ LEDs
❓ GPRS
✔️ Buttons (AUX on /dev/input/event0, power on /dev/input/event2)
✔️ Device power management (with om user space tool)
✔️ Suspend to RAM (suspend with echo mem > /sys/power/state, resume with power button)
✔️ Real-time clock
✔️ Audio on headset (alsactl restore -f /etc/alsa/headset.state)
✔️ Audio on speaker (alsactl restore -f /etc/alsa/speaker.state)
❓ Microphone
Screenshots
Splash
Login
Unsolved issues
Wrong kernel configuration
The kernel configuration is overwritten during the buildroot run, which leqds to a built kernel not matching the configuration under ̀configs/kernel. To rebuild the kernel with the correct configuration, run:
$ cp configs/kernel buildroot/output/build/linux-om-gta02-2.6.37/.config
$ make build
First buildroot build fails
The first build fails, other builds succeed:
$ make build
which: no dfu-util in (/home/clear/bin:/home/clear/bin:/usr/local/bin:/usr/bin/haswell:/usr/bin:/opt/3rd-party/bin)
make -j`nproc` -C buildroot
make[1]: Entering directory '/share/freerunner/temp/buildroot'
make[1]: *** No rule to make target '/share/freerunner/temp/buildroot/output/.br-external.mk'. Stop.
make[1]: Leaving directory '/share/freerunner/temp/buildroot'
make: *** [Makefile:20: build] Error 2
$ make build
which: no dfu-util in (/home/clear/bin:/home/clear/bin:/usr/local/bin:/usr/bin/haswell:/usr/bin:/opt/3rd-party/bin)
make -j`nproc` -C buildroot
make[1]: Entering directory '/share/freerunner/temp/buildroot'
/usr/bin/make -j1 O=/share/freerunner/temp/buildroot/output HOSTCC="/usr/bin/gcc" HOSTCXX="/usr/bin/g++" syncconfig
make[2]: Entering directory '/share/freerunner/temp/buildroot'
make[2]: warning: -j1 forced in submake: resetting jobserver mode.
...
Changelog
- next
- Switched to Linux 2.6.39 from SHR
- Move kernel features to modules loaded at boot
- Add wmiconfig
- Add Bluetooth support
- 0.3
- Buildroot 2019.02
- Linux 2.6.37
- GCC 4.9.4
- Added omhacks
- Added network configuration for usb0 and eth0
- Fixed dependencies for Xorg and fluxbox window manager
- Added U-Boot build
- Added SD card image generation
- Added U-Boot splash screen
- Added U-Boot boot menu
- Added custom boot scripts
- Added ALSA configurations for headset and speaker
- Added FAT support
- Switched to dfu-util from Buildroot
- Added screen shots
- 0.2
- Buildroot 2020.02
- Linux 3.2.99
- GCC 5.5.0
- 0.1
- Buildroot 2019.02
- Linux 2.6.37
- GCC 4.9.4